German officials say an Afghan security force member has been killed and three others have been injured during a firefight at the airport in Kabul. The unified armed forces of Germany says there have been clashes between Afghan forces and unknown assailants at the northern gate of Kabul airport. It says American and German soldiers were also involved in the clashes. NATO officials at the airport say all gates have been closed. The Kabul airport has been the scene of chaos in the past days as thousands of people rushed there in a bid to flee the country amid the Taliban takeover. More than 20 people have lost their lives due to stampedes and gunshots at the airport.